Faxx Tuba and Sousaphone Mouthpieces 18 The Faxx mouthpieces were developed as facsimiles of the more common designs at more economical prices Only the most popular numbers have been reproduced in sufficient quantities to guarantee the lowest prices possible for quality mouthpieces The Faxx mouthpieces were developed as facsimiles of the more common designs at more economical prices Only the most popular numbers have been reproduced in sufficient quantities to guarantee the lowest prices possible for quality mouthpieces